I haven't been trying to auto-farm any of the levels, but I've gotten through all but the last with this team:

-Navigator Eddie (Invisibility/Void) - Unsharded, but the troopers I have with Navigator are sharded and I use those sometimes
-Pharaoh Eddie in backup for revive/invincibility if needed
-Mystic/GRE for some magic damage
-Alliance General (All Health) - Fully sharded
-Gunner Pharaoh Dog (Invisibility/Energy) - Unsharded
-Gunner Golden Sun (Thief/Void) - Fully sharded

It can be a slog in this level since I don't bring any magus characters other than the Eddies, but the only time I've lost so far has been a time that the boss doomed 3 of my characters. It's pretty reliable for breaking the shields quickly and getting some hits on the boss.

Strategy is this: Have Navigators Fury chip away at the shield, give him an extra turn with GGS and then use the cannonballs to knock another 6 points off. Alliance General keeps the power flowing and keeps the Dragon King's fury repressed. GPD is there for healing/damage reduction/debuff removal. On the 2nd turn just use normal moves and the first shield is broken. This team generates enough fury to be in class advantage on most turns, and strategic use of Alliance General's power move can let you take a bite out of the bosses health.

I've found a working combination of "normal"-ish characters that can farm IX easily. I've beaten X with it, but it was a bit more of a pain, and could have gone either-way at points.

Team (everyone sharded):

Tailgunner/GRE: Tailgunner helps clear the waves, while GRE is used against the boss
MCR: Freeze ability is crucial against the waves
CG: all freeze tal's. Backup stun is useful against waves
GPD: Damage reduction, heal, immunity
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Ok, strat against the waves is simple - freeze them as much as possible to avoid counters and wipe them out. Fairly easy at IX, was a bit more sketchy at X.

Against the boss, the strat is the same for IX as it was for X, just far quicker on IX.

Use GRE's special to knock off the incremented shield to get to the force shield. The way it usually plays out (on IX) I can get it to two ticks with everyone's attacks (plus GRE's special). The next turn I hit it with the GPD and MCR to get to the next shield, then once with the CG to apply the lowered MR, and then GRE to open up the face.

After that I'm able to do 30-40k per turn, as long as I apply the lowered MR from CG first. It doesn't take many turns of that to finish it off.

The Clairvoyant (Sorta Farmable from Eternity Souls in the Arena - with luck)

Grim Reaper Eddie (Earned through Achievements)

Golden Pharaoh Dog (Earned through Achievements)

I've did two GoL runs on auto with almost the same team, but instead of the Gunner Pharaoh Dog, I used a Angel of Fear. Got 1 win and 1 lose, so I think I'll try next time with the GPD, but it will take longer. If it's safe, it's ok, then.